energy, a high-efficiency furnace can give you 90 cents on the dollar for the fuel you pay for, but another 25 to 40 cents on the dollar can be lost through the ductwork. >> wow. so, what you're saying is by the time you heat the living area, the typical house really could be losing about half of what they're spending on heating. >> unfortunately that's true, whether you burn natural gas, heating oil, propane or have an electric furnace. as a matter of fact, i recently shot some video for a home improvement website. i'd like to share it with your viewers. >> sure. let's, let's take a look. >> i'm here with karl balla, who is a certified home energy rater. so, tell us, karl, what are we looking at here? >> well, tony, this is a typical home, 10 years old, forced-air furnace, standard metal ductwork. >> and what is that you're holding there? >> well, this is a special infrared camera. i use it to show my clients how their homes are wasting heat.